Some aircraft were known for inflight fires; the B24, for example, with high dihedral, tended to end up with avgas in the bomb bay and was known as the "flying coffin" or the "flying incinerator."

The B29's main source of fires was at the engine, but an engine fire could spread to the wings, where the fuel is located.

The inboard engines contained the main landing gear: the gear retracted upward into and was contained by the #2 and #3 aft nacelles, aft of the firewall. Hot brakes in proximity to fuel cells, fuel lines, hydraulic lines, etc, were a potential source of trouble.

When a cylinder head lifted, which was common, it usually resulted in a large oil loss. It also pulled the pushrod tubes out, causing oil loss; the oil was a big fire hazard with a large exhaust collector, a close cowl with all the other cylinders operating. The intake tubes are several inches in diameter and carry the fuel-air mixture from the carb, which is large; they're in numerous segments and with a lifted head, the fuel-air mixture is pumped directly into the engine compartment.

The engine is supercharged and a type of turbocharged: the supercharger is the back section of the engine case and contains a large compressor gear-driven off the back of the engine. I've had the clutch or gearing fail. By comparison, I've had over 50 engine failures in flight; most of those have been large radial engines. They have a lot more issues because there's a lot more to go wrong, and they were never designed to last long, and their operational time between overhauls or major service was very low. The turbochargers were two turbochargers, referred to as turbo-superchargers, per engine. These were driven by exhaust; they were oil cooled, in the exhaust collector stream, and subject to failure.

Fuel ran through the aircraft, wing to wing, with large oil tanks (typical oil tanks in aircraft of that era were 35-60+ gallons of oil); a lot of oil to be fed to a fire. There were a lot of hydraulics on board to operate flaps, gear, brakes, etc, and the H-5606 fluid is flammable.

The B29 was unique among other bombers in that it was pressurized to allow long range high altitude flight, and had a pressurized path through the bomb bay from the front to the rear of the aircraft. It used a railed trolly that one crewmember at a time could use; lay on it and hand-over hand as it rolled from from to back or visa versa. That also meant slower egress.

Pressurization is done with "bleed air," or in the case of the B29, with turbo-superchargers. These were run electrically from the cockpit. The B29 represented the first introduction of a military aircraft to pressurization: the concept was in its infancy, as was high altitude physiology. Structural failure was a potential issue due to rupture due to damage, and the concept of pressure cycles and fatigue was all but unknown. Onboard life support equipment was inadequate and new, including oxygen masks and systems, crew clothing, etc. The crew flew higher than other crews had flown, exposing them to greater hazard in cold temperatures, coupled with the pressure differential.

Radial engines shake; it imposes stresses on the airframe unknown in modern turbine aircraft. The R3350 and later R4360 tends to be smoother than many, but there's still a lot of vibration and shaking, and fatigue going on.

Someone mentioned Darryl Greenameyers attempt to pick up a B29 in the arctic. It eventually burned as taxiing for takeoff, when a coleman generator in the back of the airplane tipped over and caught fire; the aircraft burned in place on the ice runway. It's a sad story.

I've experienced a number of onboard fires in old WWII era aircraft, including cabin cockpit and cabin fires. In the PB4Y (B24), we had tall glass fuel sight gages on the flight deck. All the fuel in the airplane came into the cockpit before being pumped under pressure back to the engines. every ignition source and every fuel and everything flammable except gear and engine oil, came through the cocpit. We had rotary inverters (sparkers), hydraulic pumps, hydraulic resorvoirs, etc, all right there in the cockpit area, as well as a Ranger V2 engine with a direct drive 400 KVA generator attached, as our auxiliary power unit. Loud. Also potentially flammable. The B29 did away with a lot of that, reducing the potential for fires inside the fuselage, but the complexity and design still had the potential for engine fires, which weren't uncommon.

The B29 was best known for hot engines and sucking valves. It couldn't spend a lot of time operating on the ground above idle, which is true of most radial engine airplanes. B29 crews learned to accelerate quickly after takeoff to get max airflow through the engines to cool them.

Typical in these engines was the use of ADI, or "anti-detonation fluid. Typically a mixture of alcohol, water, and glycol, it's injected to prevent detonation at high manifold pressure settings. High manifold pressure places a significant demand on the fitting between the cylinder head and the cylinder on the engine. Every cylinder is bolted on independently, unlike a car, and unlike a car, the head isn't bolted to the cylinder. It's held on with an interference fit, put in place on a hot cylinder. If the cylinder gets too hot, the head departs, and when it does, it can easily lead to oil loss, and a fire. Oil fires, unlike other fires, don't go out quickly and the oil can get to the wings, spar, etc.

A pressurized fuselage made the possibility of a fire on board greater: at altitude in an unpressurized airplane, fire is less likely to burn, but in a pressurized fuselage with greater oxygen partial pressure and availability, fires burn easier and more intensely.

The engines on the B29 are largely magnesium and magnesium alloy cases; this is for weight and strength, but at the expense of flammability. Magnesium can burn over 5,000 degrees and has the capability of burning through the wing in short order; an engine fire with fuel or oil burning can quickly become a metal fire, and that can't be extinguished with on board fire equipment. A magnesium fire, which could be caused by a number of things, is extremely dangerous.

B29's started the war with carburetors; Stromberg downdraft carbs, which tended to catch fire sometimes, particularly in the event of a backfire. The fuel delivery system changed during the course of the war, toward the end to a form of injection.

The supercharger itself was a source of failure, with a clutch and gearing for changing supercharger speed and output. Lots of failure points in there.

For a story, a flare set off in the aircraft that ignites hydraulics and causes a rupture of the pressure vessel might be a plausible failure point.

The B29 also has it's own reciprocating (piston engine) aux power unit in the back of the aircraft, with it's own fuel source, and a potential to catch fire (I've had it happen on several aircraft). It's remote from most of the crew, making it a potential serious problem should it be unable to be controlled.

Based on the book Hells Angels, about B17's in Europe there were stories in which Generals flew as co-pilots on combat missions, pilots being capt and majors. One funny story in which that had to actually restrain one general who freaked out on a mission.

As to B-29's, my dad was attached to the 509th after the war, only thing he did was run up the B29's, set one on fire, oil would fill up the bottom jugs. He was acting as flight engineer, and from what I remember they sat against the fuselage and controlled the extinguishers.

quote:

Originally posted by RHINOWSO:

quote:

Originally posted by parabellum:
Thanks very much guys.

Would the path for a B-29 pilot have been OCS, then flight school, then straight to flying a B-29? Or would the path be different, including first serving in smaller aircraft?

Unlike today, in WW2 an Army Air Corps officer commission was usually tied to successfully completing flight training - normally you were an aviation cadet until getting your wings, then you were also commissioned as an officer / 2LT or Warrant Officer. Reason being they didn't want you as an officer if you didn't fly. So officer / indoc training was combined to a degree with flight training. Obviously there were West Point grads and other commission officers that went to flight training after getting commissioned, but the large majority of pilots weren't commissioned until complete with flight training.

After flying a number of training planes and getting their wings, new pilots were then funneled to Bomber / Fighter / Cargo specific training.

As recently as thirty years ago (‘89), the Navy had two tracks for folks who had not done ROTC or the Naval Academy - AOC (Aviation Officer Candidate) and NavCad (Naval Cadet). Those with a four year degree were eligible for the AOC program, those with a two year degree were eligible for the NavCad program. Generally, AOC were E5s during the 14 week program (training on how to be an officer and the basic bookwork of Aerodynamics, Engines, and Navigation) and were commissioned as officers (O1, ensign) in the US Naval Reserve upon graduation. NavCad went through the exact same program, but as E1s. They went off to flight school just like their AOC classmates, but were not commissioned until they earned their wings.
I don’t know whether or nor these programs are still active, but it wouldn’t surprise me.

My father was a "radio man" on a B29 at the end of the war. He entered service with the Army Air Corp with a college degree & a civilian pilots license, but was never an officer.

He is the one on the right

What a great thread!

Thanks to all who’ve contributed.

quote:

Originally posted by smlsig:
What a great thread!

Thanks to all who’ve contributed.

I was just about to post the same sentiment so I'll 'second' yours...really enjoying this thread and all the info shared.

quote:

Originally posted by slosig:
AOC (Aviation Officer Candidate) and NavCad (Naval Cadet)... ...I don’t know whether or nor these programs are still active, but it wouldn’t surprise me.

I ran into some of the last of the NavCads during my time - they were all senior to me and the program itself was ended in the early 90s.

These days in the Navy, its all commissioning before flight school, either via Naval Academy, ROTC, or OCS (no AOCS anymore, although you can get Aviation out of OCS but they don't have a separate school).

If you wash out of flight school, they look at what else they need and you go there (ships, supply, intel, etc.).

I will say that these days its not uncommon for a senior officer to not be leading a flight of fighters - sometimes they are just back from being out of the cockpit for awhile, are a guest / staff officer, or need to let the junior officers lead for training / experience. Even in combat we would have juniors lead flights - if they were qualified to lead, they could lead.

At least in Navy Fighters, rank comes off in the cockpit for the most part, although the senior officer still has overall flight responsibility and can step in as needed but typically they won't. Aircrew use callsigns for everyone but the Commanding and Executive officer, but even then they are "Skipper" / "XO", not "Commander Smith", etc.

Of course 1 and 2 seat fighters is different than multicrew bombers / patrol planes.

quote:

Originally posted by parabellum:
All good stuff, thanks, guys. This is research for short story, in case anyone is wondering why I'm asking these questions.

Para, I was just wondering if you ever finished your short story, and if so, is it published somewhere we might read it?

B29 shot full of holes over Japan. They were tough birds, Iwo Jima saved so many lives

Memoirs of WW II

quote:

Originally posted by HayesGreener:
There were also "Flying Sergeants" in the USAF who flew as pilot in command of all types of aircraft. Carroll Shelby was one of them.

Some flying sergeants became aces. I was on active duty when one of the last flying sergeants retired. So, it seems the USAF recognized skill and ability were more important than rank. Still true today. I have been on USAF aircraft where the aircraft commander is a Lt or Captain and the co-pilot is a Lt Col.

My father was a Pilot Sgt.1944-45 He also manned Top Turret Guns

quote:

Originally posted by slosig:

As recently as thirty years ago (‘89), the Navy had two tracks for folks who had not done ROTC or the Naval Academy - AOC (Aviation Officer Candidate) and NavCad (Naval Cadet). Those with a four year degree were eligible for the AOC program, those with a two year degree were eligible for the NavCad program. Generally, AOC were E5s during the 14 week program (training on how to be an officer and the basic bookwork of Aerodynamics, Engines, and Navigation) and were commissioned as officers (O1, ensign) in the US Naval Reserve upon graduation. NavCad went through the exact same program, but as E1s.

My experience with NavCad:

When I was USN, late 1950s, I was regular enlisted. We were allowed to apply for NavCad. I did apply. I was E-5 at the time (guided missile nerd).

The process, I completed a request form, got it approved through the chain of command (my division officer, XO, and up from there). Then, there was a fleet-wide written exam. Top qualifiers on the written exam -- I was one -- received provisional orders to enter the program, via the nearest Navy medical facility, where I was immediately disqualified when they told me to take my glasses off and read the chart on the wall.

Distant vision in my right eye, was 20/400 uncorrected.

Later, once out of the Navy, in order to qualify for the grade of medical certificate needed for Commercial Pilot, I had to go through the process of getting a Certificate of Demonstrated Ability, informally known as a "Waiver," which I did, ironically through a retired Navy Flight Surgeon.

Still later, as a Geezer, I had cataract surgery, and the implanted lens corrected my distant vision to 20/20, so my vision now would qualify for Naval Aviation, but they don't accept octogenarians into the program.

Stephen Ambrose's book, "The Wild Blue", goes into the training and command/crew structure (B-24's) quite a bit.